Smogless combustion apparatus

ABSTRACT

An improved smogless incinerator for combustible waste materials includes a plurality of chambers through which the combustion products are drawn for successive filtering. The combustion products are filtered through a liquid which is maintained in a turbulent condition by forced air bubbling through the liquid along with the combustion products to assure complete entrapment of the partial combustion products within the liquid.

United States Patent 1191 Graves Mar. 26, 1974 SMOGLESS COMBUSTION APPARATUS [76] Inventor: Willa A. Graves, 2213 Radio Ave.,

San Jose, Calif. 95125 [22] Filed: May 4, 1972 [21] Appl. No.: 250,281

52 us. or. ..110/s R, 110/75 R, 110/119,

261/121 R, 55/223, 55/256 51 1m. (:1. ..F23g 3/00 58 Field of Search 110/8 R, s A, 119, 18 R,

[56] References Cited UNITED STATES PATENTS 3,572,264 3/1971 Mercer 34/119 3,504,481 4/1970 Zakarian et al.. 55/223 3,566,583 3/1971 Ashmore 55/256 3,520,113 7/1970 Stokes 55/223 2,212,311 8/1940 Alfisi 110/75 B 2,095,568 10/1937 McKeown 110/75 B Primary Examinerl(enneth W. Sprague Assistant Examiner-James C. Yeung ZitorfiEyTHgEiifoF Firm- Claude A. S/Hamn'ck,

Thomas E. Schatzel and Schatzel & Hamrick 5 7] ABSTRACT An improved smogless incinerator for combustible waste materials includes a plurality of chambers through which the combustion products are drawn for successive filtering. The combustion products are filtered through a liquid which is maintained in a turbulent condition by forced air bubbling through the liquid along with the combustion products to assure complete entrapment of the partial combustion products within the liquid.

4 Claims, 8 Drawing Figures PAIENTEBmzeum 3.799.076

SHEEI 1 0F 3 PAIENTEDIMRZB m4 sum 2 or 3 Z3*I I F1 2 FBI) FULL ADD 19 13 igure 4 igure 6 II I 'I l I I 'I I 'I 'l J I I I II U F"! I L .J

I l II II II II I I l I l 1 I l l I I J SHEET 3 [IF 3 PAIENTEU M826 I974 L .JL

IIIIIIIIIIIIIIIIIIL I l I l l l l I I I l l I I I I L SMOGLESS COMBUSTION APPARATUS BACKGROUND OF THE INVENTION Certain known incinerators use recirculation of the combustion products through auxiliary flame apparatus to assure that airborne particles from the initial combustion are consumed in subsequent combustion chambers. Incinerators of this type usually require a source of fuel to maintain the auxiliary flame through which combustion products from the combustion chamber may be drawn for more complete combustion. In addition, the fuel used to maintain the auxiliary flame is required to burn relatively cleanly to assure that the auxiliary flame does not contribute undesirable airborne combustion products of its own. These known devices have the disadvantage that they are not useful for domestic purposes because of their relative complexity and lack of portability due to the requirement of a connection to a fuel supply.

SUMMARY OF THE INVENTION The incinerator apparatus of the present invention includes a pair of filter chambers disposed above a combustion chamber. Each filter chamber contains a supply of liquid through which the combustion products to be filtered are drawn. Each chamber includes a gas duct disposed beneath the surface of the liquid and also includes an air outlet disposed beneath the gas duct within the supply of liquid. Air supplied to the outlet under pressure causes turbulence of the liquid in and about the gas duct. The turbulence in the liquid enhances the mixing of the partial combustion products from the combustion chamber with the liquid to assure that airborne particles from the combustion chamber are trapped in the liquid. In addition, the liquid is forced to bubble through a perforated baffle plate to ensure further prolonged contact of airborne particles with the liquid.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a front view of the smogless incinerator according to the present invention;

FIG. 2 is a side view of the apparatus of FIG. 1;

FIG. 3 is a plan view of the baffle plate in the apparatus of FIG. 1;

FIG. 4 is a front view of the apparatus of FIG. 1 disposed within an enclosure;

FIGS. 5(a), (b), and (c) are, respectively, front, side and rear views of the air inlet to the combustion chamber of the apparatus of FIG. 1; and

FIG. 6 is a side sectional view of the air inlet chamber of the apparatus of FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to FIGS. 1 and 2, there are shown front and side views, respectively, of the smogless incinerator according to the present invention. A combustion chamber 7 disposed in the lowermost region of the present invention includes a generally rectangular volume which includes a floor grate 40 positioned over an ash collection bin 42. The ash collection bin 42 includes a drawer 44 which may be pulled out in order to remove ashes from the combustion chamber. Air for supporting combustion within the chamber 7 is drawn in through the inlet port 46 which is positioned in the front face of the apparatus. Air is supplied to the combustion chamber through the valve 9, the inlet chamber 17, and the air channels 48 and 50 disposed around the frontal opening of the combustion chamber 7. Details of the air inlet system according to the present invention are described in greater detail hereinafter with respect to FIG. 5. The combustion chamber may comprise substantially the entire lower portion of the structure of FIG. 1 although, as illustrated, the combustion chamber 7 is merely shown centered within the lower portion of the apparatus. It is intended that the present invention be used for incinerating combustible waste materials such as paper, cardboard, plastic, wood products and the like. It should be understood, however, that where desirable a fuel supply such as natural gas may be supplied to the combustion chamber 7 as through a gas burner positioned beneath the floor grate 40 within the combustion chamber in order to incinerate such waste materials as fruit and vegetable peels, meat products, and the like; that are normally not readily combustible in a self-sustaining combustion system.

The combustion products from combustion of waste materials in chamber 7 including airborne particles representative or partially incinerated waste materials are drawn from the rearward portion of combustion chamber 7 through the exhaust duct 14, as shown in the side view of FIG. 2. A blower 10 is included along the exhaust duct 14 to provide a pressure differential between the combustion chamber 7 and ambient air pressure supplied to the combustion chamber through the inlet port 46. The blower 10 also provides a sufficient amount of air pressure to force the combustion products exhausted from the combustion chamber 7 into the first filtering chamber 50. The exhaust duct 14 may be formed into a U-shaped trap 41 to collect liquid distillates that may be derived from combustion of waste materials in the combustion chamber 7.

The first and second filter chambers 50, 52 are disposed above the combustion chamber 7 and comprise substantially the entire upper portion of the structure of the present invention. These filter chambers 50, 52 are separated by a gas baffle 54 which is substantially centrally disposed within the upper portion of the apparatus of FIG. 1. Each of the chambers 50 and 52 is partially filled with a common supply of a liquid such as water 3. The exhaust duct 14 is connected to the first filter chamber 50 through the blower 10 and a gas duct 56 which includes a plurality of perforations 25 that are disposed beneath the surface of the liquid 3. This assures that all combustion products entering the chamber 50 must pass through the duct 56, the apertures 25 and up through the liquid 3 to the region above the liquid surface. A perforated baffle plate 13 is disposed substantially horizontally beneath the surface of the liquid 3 and just above the gas duct 56. Also, filters 5 and 6 are positioned in successive layers above the surface of the liquid 3 within the first chamber 50. These filters 5, 6 provide successive stages of filtration through such filtering materials as glass wool, charcoal granules, and the like, to assure adequate filtration of airborne particles from the air within the chamber 50.

The gases present in the upper portion of the first filter chamber 50 are drawn from the chamber via the duct 58 by blower l5 and are returned through the return duct 60 to both'the first and-the second chambers. The outlets 16 of the return-duct 60 into each of the filter chambers 50, 52 are positioned beneath the associated gas duct 56, 64 within the corresponding chamber 50, 52. This ensures that the gases returning to the filter chambers under pressure when released beneath the surface of the liquid 3 will produce turbulence in the liquid 3 surrounding the perforated gas ducts 56 and 64. In this way, air and combustion gases that are present within the upper portion of chamber 50 are recirculated through the liquid 3 after initially bubbling through the liquid into the chamber 50 from the gas duct 56. The turbulence thus produced in the liquid 3 within the chamber 50 aids in preventing accumulation or sedimentation of airborne particles at the bottom of the chamber and also maintains these partial combustion products suspended in the liquid 3 during operation of the present apparatus. A perforated baffle plate 13, as shown in FIG. 3, is disposed immediately above the gas duct 56 to establish an effectively longer path length through the liquid 3 for the air bubbles from the return duct 60 and the gas duct 56 as these bubbles and the airborne particles entrained therewithin rise to the surface of the liquid 3. The perforations 80 in the baffle plate 13 aid in mixing the airborne particles and the liquid 3 as the turbulent flow of aerated liquid passes through the perforations 80 in the baffle plate 13 toward the surface of the liquid. In addition, the baffle plate 13 assures that turbulent action occurs predominantly below the plate and that liquid motion above the baffle plate will remain relatively calm, thereby avoiding unnecessary splashing and possible contamination of the air-filtering materials disposed in layers 5, 6 above the surface of the liquid 3. The locations of the apertures 80 in the baffle plate 13 are not critical but are desirably disposed remotely from the immediate vicinity above the gas duct 56, 64 to assure that combustion products introduced into the liquid 3 through the perforations 25 in the gas duct 56, 64 will remain in contact with liquid 3 over a longer course of travel through the liquid to the surface. And, to assure that the liquid 3 remains in the chamber 50 in the absence of air pressure supplied by blowers 10 and 15, the upper ends of each of the ducts 56, 60 and 64 are maintained above the surface level of the liquid 3.

A second gas outlet 62 larger than the duct 58 is provided at the upper region of the first filter chamber 50. A blower 11 attached to this outlet 62 forces the air and combustion gases present in the upper region of the first filter chamber 50 down into the gas duct 64 which is disposed beneath the surface of the liquid 3 in the second filter chamber 52. The construction of this second filter chamber 52 is similar to the construction of the first filter chamber 50, as previously described, with the exception that the blower supplies to the second filter chamber 52 the air and combustion gases that are drawn only from the first filter chamber 50 via the duct 58 in that chamber 50. Thus, the second filter chamber 52 operates substantially as described previously in connection with the operation of filter chamber 50. Air and combustion gases that accumulate above the surface of liquid 3 in chamber 52 are drawn off through outlet 66 which may be coupled to an additional blower 12 that aids in forcing circulation of air and combustion gases through the chambers 50 and 52.

Referring now to the front view of FIG. 4, there is shown the apparatus of FIG. 1 contained within an enclosing housing 70. The housing includes a frontally located door 27 including a window 21 for viewing combustion within the chamber 7 and including a door latch 20 for securing the door 27 against undesirable accumulations of gas pressure within the chamber 7. The combustion air inlet 46 is positioned adjacent the door 27 to aid in cooling the front portion of the combustion chamber in a manner as later described herein. The level of the liquid 3 within the chambers 50, 52 may be observed through viewing window 19 which communicates with the inner walls of the chamber 50. It should be understood that the liquid levels may be maintained independently in the chambers 50 and 52 simply by providing a liquid-tight, vertically disposed baffle plate 54 between the chambers 50, 52 as shown in FIG. 1. Under these circumstances, a separate liquidlevel viewing window 19 and a separate filling spout 18 should be provided for each chamber to assure that the liquid levels may be properly and conveniently maintained. The enclosure also includes the single outlet 23 arranged at the uppermost portion of the enclosure as the only exhaust port for the apparatus of the present invention. Connection to a source of electric power is required and a control switch 22 for the'blowers is provided at a convenient location on the enclosure.

Referring now to the front, side and rear views shown in FIGS. 5(a), (b) and (0), respectively, and to the partial sectional view of FIG. 6, there is shown the air inlet system of the present invention. As previously indicated, the combustion air, and hence the air that is circulated throughout the apparatus of the present invention, is admitted into the combustion chamber 7 through the inlet port 46 placed in the near vicinity of the door to the combustion chamber 7. The air which is admitted through this inlet port 46 passes through a flapperor check-valve 9 into the inlet chamber 17. The check-valve 9 prevents undesirable backfire through the inlet port 46 under circumstances of undesirable buildup of combustion gases within chamber 7. The inlet chamber 17 is enclosed and has an outlet of air passage 48 positioned in the hollow frame 8 that surrounds the door into the combustion chamber 7. This frame may conveniently be formed of hollow steel tubing to form a tuyere system about the front portion of the combustion chamber adjacent the door 27. This tuyere system .thus supplies combustion air to the combustion chamber 7 through the apertures 51 that may be provided about the doorway between the hollow steel frame and the volume of the combustion chamber, as shown in FIG. 1. Alternatively, combustion air may be admitted into the chamber 7 through an elongated aperture 53 which is disposed intermediate the chamber 7 and the ash collection bin 42, as shown in FIG. 5. Air admitted into the combustion chamber in this manner thus aids in cooling the frame around the door 27 to the combustion chamber 7 and thereby assures that sustained combustion within the chamber will produce only negligible temperature rise in the region of the door 27. This facilitates safe handling of the present invention during operation and assures that the door 27 may be opened with minimal risk of burn or injury to the operator. In addition, the tuyere system disposed about the combustion chamber in accordance with the present invention provides sufficient combustion air from distributed locations about the combustion chamber to ensure more complete combustion of waste materials.

Therefore, the incinerator apparatus of the present invention provides multiple filtration of the combustion products during the incineration of waste materials and assures substantially smogfree consumption of such waste materials without the added expense of supplemental or auxiliary fuel supplies. In addition, the partial combustion products and airborne particles commonly associated with incineration of waste materials are entrapped within a liquid filtration phase of the present invention to be conveniently disposed of as liquid waste material. In addition, the thermodynamic design of the combustion chamber assures that combustion air admitted to the combustion chamber may provide cooling of the surrounding structure for enhanced operator safety and for more complete combustion of waste materials. Further, sustained operation of the present invention in incinerating waste materials heats the filtering liquid by direct conduction through the upper wall of the combustion chamber for enhanced solubility of airborne combustion products in the liquid.

I claim:

1. Incinerator apparatus for disposing of combustible waste material, the apparatus comprising:

a combustion chamber having an inlet for admitting combustion air and having an outlet;

a plurality of filter chambers, each having a gas inlet and a gas outlet;

first duct means connecting the outlet of the combustion chamber to the gas inlet of one of said filter chambers;

second duct means connecting the gas outlet of said one filter chamber and the gas inlet of another filter chamber;

at least one of said filter chambers including a quantity of liquid therein which covers the gas inlet to such chamber; and

gas re-circulating means connected to the filter chamber having liquid therein for exhausting therefrom a portion of the gas present in such filter chamber above the surface of the liquid therein and for re-introducing the exhausted gas under pressure into said filter chamber having liquid therein beneath the surface of the liquid.

2. Incinerator apparatus as in claim 1 wherein:

said gas re-circulating means includes an outlet disposed within said one filter chamber at a location which is beneath the surface of said liquid therein and which is substantially beneath the gas inlet for said one filter chamber; and

a baffle plate is disposed substantially horizontally within said liquid at a level which is intermediate the gas inlet for said one filter chamber and the surface of said liquid.

3. Incinerator apparatus as in claim 1 wherein:

' each of said filter chambers include a quantity of liquid therein which covers the gas inlet to such chamber;

each of said chambers includes a baffle plate having a plurality of apertures therethrough positioned substantially horizontally within the liquid at a level which is intermediate the gas inlet and the surface of the liquid; and

said gas re-circulating means is connected to exhaust the gas present above the surface of the liquid in one of said filter chambers and for introducing the exhausted gas under pressure to each of said filter chambers having liquid therein via outlet means disposed beneath the gas inlets to such filter chambers.

4. Incinerator apparatus as in claim 2 wherein:

said gas inlet for said one filter chamber includes a plurality of perforations for admitting gas therethrough into said liquid;

said one filter chamber includes gas-permeable filtering means disposed above the surface of the liquid for passing gaseous combustion products therethrough and for blocking passage therethrough of particulate combustion products; and

said gas re-circulating means includes a port positioned above said gas-permeable filtering means for exhausting from said filter chamber having liquid therein the gas present above said gaspermeable filtering means. 

1. Incinerator apparatus for disposing of combustible waste material, the apparatus comprising: a combustion chamber having an inlet for admitting combustion air and having an outlet; a plurality of fIlter chambers, each having a gas inlet and a gas outlet; first duct means connecting the outlet of the combustion chamber to the gas inlet of one of said filter chambers; second duct means connecting the gas outlet of said one filter chamber and the gas inlet of another filter chamber; at least one of said filter chambers including a quantity of liquid therein which covers the gas inlet to such chamber; and gas re-circulating means connected to the filter chamber having liquid therein for exhausting therefrom a portion of the gas present in such filter chamber above the surface of the liquid therein and for re-introducing the exhausted gas under pressure into said filter chamber having liquid therein beneath the surface of the liquid.
 2. Incinerator apparatus as in claim 1 wherein: said gas re-circulating means includes an outlet disposed within said one filter chamber at a location which is beneath the surface of said liquid therein and which is substantially beneath the gas inlet for said one filter chamber; and a baffle plate is disposed substantially horizontally within said liquid at a level which is intermediate the gas inlet for said one filter chamber and the surface of said liquid.
 3. Incinerator apparatus as in claim 1 wherein: each of said filter chambers include a quantity of liquid therein which covers the gas inlet to such chamber; each of said chambers includes a baffle plate having a plurality of apertures therethrough positioned substantially horizontally within the liquid at a level which is intermediate the gas inlet and the surface of the liquid; and said gas re-circulating means is connected to exhaust the gas present above the surface of the liquid in one of said filter chambers and for introducing the exhausted gas under pressure to each of said filter chambers having liquid therein via outlet means disposed beneath the gas inlets to such filter chambers.
 4. Incinerator apparatus as in claim 2 wherein: said gas inlet for said one filter chamber includes a plurality of perforations for admitting gas therethrough into said liquid; said one filter chamber includes gas-permeable filtering means disposed above the surface of the liquid for passing gaseous combustion products therethrough and for blocking passage therethrough of particulate combustion products; and said gas re-circulating means includes a port positioned above said gas-permeable filtering means for exhausting from said filter chamber having liquid therein the gas present above said gas-permeable filtering means. 